Identification of ejaculated proteins in the house mouse (Mus domesticus) via isotopic labeling

<p>Abstract</p> <p>Background</p> <p>Seminal fluid plays an important role in successful fertilization, but knowledge of the full suite of proteins transferred from males to females during copulation is incomplete. The list of ejaculated proteins remains particularly scant in one of the best-studied mammalian systems, the house mouse (<it>Mus domesticus</it>), where artificial ejaculation techniques have proven inadequate. Here we investigate an alternative method for identifying ejaculated proteins, by isotopically labeling females with ¹⁵N and then mating them to unlabeled, vasectomized males. Proteins were then isolated from mated females and identified using mass spectrometry. In addition to gaining insights into possible functions and fates of ejaculated proteins, our study serves as proof of concept that isotopic labeling is a powerful means to study reproductive proteins.</p> <p>Results</p> <p>We identified 69 male-derived proteins from the female reproductive tract following copulation. More than a third of all spectra detected mapped to just seven genes known to be structurally important in the formation of the copulatory plug, a hard coagulum that forms shortly after mating. Seminal fluid is significantly enriched for proteins that function in protection from oxidative stress and endopeptidase inhibition. Females, on the other hand, produce endopeptidases in response to mating. The 69 ejaculated proteins evolve significantly more rapidly than other proteins that we previously identified directly from dissection of the male reproductive tract.</p> <p>Conclusion</p> <p>Our study attempts to comprehensively identify the proteins transferred from males to females during mating, expanding the application of isotopic labeling to mammalian reproductive genomics. This technique opens the way to the targeted monitoring of the fate of ejaculated proteins as they incubate in the female reproductive tract.</p

Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement

This review provides an overview of the involvement of the corpus callosum (CC) in a variety of developmental disorders that are currently defined exclusively by genetics, developmental insult, and/or behavior. I begin with a general review of CC development, connectivity, and function, followed by discussion of the research methods typically utilized to study the callosum. The bulk of the review concentrates on specific developmental disorders, beginning with agenesis of the corpus callosum (AgCC)—the only condition diagnosed exclusively by callosal anatomy. This is followed by a review of several genetic disorders that commonly result in social impairments and/or psychopathology similar to AgCC (neurofibromatosis-1, Turner syndrome, 22q11.2 deletion syndrome, Williams yndrome, and fragile X) and two forms of prenatal injury (premature birth, fetal alcohol syndrome) known to impact callosal development. Finally, I examine callosal involvement in several common developmental disorders defined exclusively by behavioral patterns (developmental language delay, dyslexia, attention-deficit hyperactive disorder, autism spectrum disorders, and Tourette syndrome)

Time-probabilistic approach to the late Miocene Messinian salinity crisis: Implications for a disconnected Paratethys

The late Miocene Messinian salinity crisis was an evaporitic episode that occurred throughout the Mediterranean; it concluded with a transition from hypersaline to fresher-water “lake sea” (Lago Mare) conditions prior to the Pliocene. Whereas numerous researchers propose that Lago Mare sediments accumulated in a Mediterranean-wide lake filled with Paratethyan waters, other workers reject this hypothesis. Here, to test this Paratethyan-overflow model, we develop a novel time-probabilistic approach to evaluate the distribution of precession-related deposits. We apply our methodology to 24 circum-Mediterranean sites, focusing on two previously untested parameters: the probability of preserving intrabasin precession cycles; and the similarities in interbasin preservation. Our results, which show an increase in preservation and similarity in successively younger cycles, display a trend opposite to what is expected from a flooded Mediterranean. Consequently, we conclude that Lago Mare accumulations were deposited in disconnected, shallow lacustrine environments, thereby casting doubt on the widely accepted Paratethyan-supply hypothesis

Self-esteem, self-prediction, and living up to commitments

In this chapter, we examine the role of self-esteem in complex self-regulation. Although high self-esteem genelally is associated with superior self-regulation (Bandura, 1989; Taylor, 1989). we present evidence indicating that high self-esteem may interfere with self-regulation when self-esteem is threatened. We propose that an optimal level of self-esteem is important for successfully making and living up to commitments. The Need for Self-Regulation Self-regulation occurs when behavior is more guided by internal standards and expectations than by situational contingencies, cues, or guides (Bandura, 1989; Carver &amp; Scheier, 1981; Kirschenbaum, Tomarken, &amp; Humphrey, 1985). Individuals self-regulate when they set their own goals and standards, and try to attain these goals and standards (Scheier &amp; Carver, 1988). Thus, complex selfregulation involves the making and keeping of cornmitments. The attainment of goals and keeping of commilrnents depends upon an accurate knowledge of personal abilities and the setting of realistic goals (Sandelands, Bmkner, &amp; Glynn, 1988). Overestimating or under-estimating one&apos;s abilities can impede self-regulation. A good analogy is the notion of bidding for a building project. The goal is to bid as close to actual costs as is possible (allowing for a modest profit). If one bids too low, the actual costs are likely to surpass the amount bid, resulting in a monetary loss. A striking example of this fallacious bidding strategy recently occurred at William James Hall at I-kirvard University when an asbestos abatement contractor had to forfeit a $25,000 deposit because the company realizedafter winning the bid-that they would lose money if they actually performed the work. On the other hand, bidding too high is likely to result in more realistic competitors being granted the project, again resulting in monetary loss. Similarly, setting goals that are far beyond one&apos;

Stirring in 3-d spherical models of convection in the Earth's mantle

On a global scale basalts from mid-ocean ridges are strikingly more homogeneous than basalts from intraplate volcanism. The observed geochemical heterogeneity argues strongly for the existence of distinct reservoirs in the Earth's mantle. It is an unresolved problem of Geodynamics as to how these findings can be reconciled with large-scale convection. We review observational constraints, and investigate stirring properties of numerical models of mantle convection. Conditions in the early Earth may have supported layered convection with rapid stirring in the upper layers. Material that has been altered near the surface is transported downwards by small-scale convection. Thereby a layer of homogeneous depleted material develops above pristine mantle. As the mantle cools over Earth history, the effects leading to layering become reduced and models show the large-scale convection favoured for the Earth today. Laterally averaged, the upper mantle below the lithosphere is least affected by material that has experienced near-surface differentiation. The geochemical signature obtained during the previous episode of small-scale convection may be preserved there for the longest time. Additionally, stirring is less effective in the high viscosity layer of the central lower mantle [1, 2], supporting the survival of medium-scale heterogeneities there. These models are the first, using 3-d spherical geometry and mostly Earth-like parameters, to address the suggested change of convective style. Although the models are still far from reproducing our planet, we find that proposal might be helpful towards reconciling geochemical and geophysical constraints